Heater



ug- 20, 1929- R. N. EHRHART HEATER Filed June 13. 1922 INVENTOR l M l Mm;

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Patented Aug. 20, 1929.

UNITED STATES PATENT OFFICE.

RAYMOND N. EHRHART, OF EDGEWKOOD, PENNSYLVANIA, ASSIGNOR TO ELLIOTT COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

HEATER.

Application led .Tune 13,

The piesent invention relates broadly to heaters and more particularly to liquid heaters or feed-water heaters for use with power plants or the like.

It has heretofore been proposed to use liquid heaters of a type similar tothe construction of condensers which utilize spray nozzles for dividing up the liquid into fine particles into which the heating vaponis admitted. This results in a thorough mixing of the heat-ing medium and the finely divided liquid whereby effective. heating is secured. Heaters of this type have, however, not been generally successful due to the variations in the flow of liquid.

In condensers, a. construction embodying a series of spray nozzles is feasible for the reason that practically a constant amountpf liquid is sprayed. In condenser practice the problem is usually to maintain the highest possible vacuum and coincidentally to spray the normal amount of liquid at all times. In liquid heaters for example of the feed water type, it is necessary to so proportion the same that there will be an etlicient heat interchange with great variations in the volume of flow of the liquid to be heated. Spray nozzles of the type referred to, which may consist of cylindrical passages each having located therein a helical vane to give rotary motion to the liquid, require a certain velocity therethrough if a suiiicient rotary motion to effectively break up the liquid is to be imparted thereto. It has been found that about a four foot head of water is necessary to make nozzles of this type spray effectively.

It not infrequently happens that the liquid to be heated in liquid heaters is under a low pressure. In other words, the liquid supply instead of being at a pressure of from ten to fifteen pounds is frequently delivered Yto the heater at a pressure of but a few pounds. Assume, for example, the use of a heater of the condenser type in which there is a set of nozzles for spraying the liquid to be heated into a stream of heated vapor. If there is a pressure of .four pounds available for the liquid, this is ample to produce the desired spray when passing the full amount of liquid through the spray nozzles. If, however, the amount of liquid is diminished to one-fourth of the normal amount, the pressure drop through the spray 1922. Serial N0. 568,054.

nozzles would diminish as the square of the amount of the liquid passed, or one-sixteenth of the normal pressure difference. This means that with a small amount of liquid passing through the nozzles under the conditions recited, there would only be an absorption of pressure of one-fourth of a pound. This would not be sufficient to break up the liquid into such a spray that heat could easily be communicated thereto by the heating medium.

If a heater is so proportioned that there is a pressure loss through the spray nozzles of four pounds with, for example, onefourtli of the normal amount of liquid passing therethrough, a sixty-four pound pressure drop through the nozzles would be required if the full amount of liquid flows therethrough. Obviously suchv a pressure would be prohibitive in the case of most heater installations.

All of the foregoing problems have been encountered in the construction of liquid heaters of this general type with the result that the operation of such heaters has been generally unsatisfactory. By the present invention there is providedv a comparatively simple heater construction which eifectively overcomes the diliculties heretofore encountered and Which efficiently breaks up the liquid to be heated.

The accompanying figure of the drawings illustrates diagrammatically one embodiment of the present invention, it being understood that the particular construction and arrangement of the parts is immaterial and that changes may be made therein without departing from the spirit of the invention or scope of my broader claims.

In accordance with the present invention there may be provided a heater comprising generally a heating chamber 2 of any desired construction having a suitably located inlet 3 for the heating medium. This medium in heaters of this type may be conveniently in yvapor form such as steam. Below the heater 2 may be provided a receptacle 4 adapted to contain the heated liquid. This liquid may be drawn as required through a suitable outlet 5.

For effectively carrying out the present invention, I preferably provide a series of spray nozzles which may be divided into any desired number of groups. In the drawings,

I have illustrated an upper group 6 and a lower group 7. The exact number and arrangement of these groups is, however, immaterial. Communicating with each group of nozzles for supplying thereto the liquid to'be heated is a header 8, these headers being supplied from a main supply pipe .9 through branch connections 10. Within each of the branches there may be provided i controlling valve of any desired construction adapted to be operated by the crank arms 11-and 12.

It the normal amount oli' liquid is to be heated, both of the valves may be opened as tha available pressure will be sutlicient to eilectively spr-ay the liquid into the heating medium and break up the same in such manner that an eliicient heat interchange will take place. On the other hand, if the level it the liquid in the receptacle falls below normal the crank arm 12 may be moved into the vposition illustrated in full lines in the drawing to cut oli the supply of liquid to the spray nozzles 7. rllhis will temporarily cut these nozzles out of operation and thereby increase theavailable effective pressure for forcing the liquid through the nozzles 6. In this manner there is always maintained an ethcient operating condition. In actual practice it is desirable to automatically control the operation of the valves, and for this purpose I may provide a float 13 operatively connected to a link 14 in such manner as to raise the same as the level of .the liquid in the receptacle 4 lowers and to lower the same as the level therein rises. rIlhe link 14 'mayhave secured to its upper end a pivotally connected extension 15 which is in turn pivot-ally connected to the crank arm y11. By this means the arm 11 will be moved in accordance with variations in the liquid level in the receptacle 4 tor correspondingly varying the flow vthrough the valve controlled thereby. For operating the'crank arm 12, by the movement ofthe Vlloat 13, the link 14 may be provided with a lost motion connection 16 with the crank arm 12. Vith this construction the valves will be serially opened to control the admission o'f liquid to the heater in proportion to `the amount withdrawn through the outlet .5.Y VIn other words, if the demands for heated liquid are low, the float v13 will only drop slightly thereby slightly opening the valve controlled by't-he crank arm 11. VIf the demand increases the continued movement of the link 14 will be effective for opening the Vvalve controlled "by the Vcrank arm 12. As the demands .again decrease the valves will be rclosed inthereverse order, as will be clearly understood. It will-beo'bvious that by this same means it is possible to serially open-any desired number ofvalves in accordance with the number of groups of nozzlesV provided.

"with demands upon the heater whereby an effective breaking up of the liquid to be lheated and an elicient interchange is always insured.

I claim:

1. In a liquid heater, means for effecting substantially uniform heating of a'quantity of water variable in accordance with demands on the heater,said means comprising a plurality ofgroups of nozzles for spraying the liquid into the heater, means ltor supplying a liquid to each of'said groups, and means controlled by demands on the heater for-rendering at least one of said groups inoperative while the remaining nozzles are operative,.substantially as described. v

2. In a liquid heater, means for effecting substantially uniform heating of a quantity of water variable in accordance with demands on the heater, said means comprising a plurality of groups of nozzles for spraying the liquid into the heater, means .for supplying a liquid to each ot said groups, and

means for automatically rendering at least one of said groups inoperative while the remaining nozzles are operative, substantially as described.

3. In aliquid heater, a plurality oli' spray nozzles for spraying liquid, and means responsive to demands on the heater for increasing in regular sequence the number of act-ive nozzles as the low of liquid is increased 'or decreased, substantially as described.

4. -In a liquid heater, avplurality ofspray nozzles for spraying liquid, and float .operated means `for automatically increasing or decreasing the number of active nozzles as the flow of liquid is increased or decreased, substantially as described.

5. In a liquid heater, a plurality of spray nozzles 'for spraying the liquid to be heated, land means responsive to vdemands on the he'ater and operative in proportion to the amount Yof Aliquid being -heated for varying the number oi' active spray nozzles, substantially as described.

6. Ina-liquid heater, aplurality' of spray nozzles Vfor spraying the liquid Vtobe'heated, and float operated Vmeans orautomatically varying the'number of active spray nozzles v in proportion to .the 'amount of liquid lbeing heated, substantially as described.

7. In la liquidh'eater, means for eil'ecting substantially uniform heating of .a quantity of water variable vin accordance with demands on the heater, said'mean's comprising a plurality of groups of nozzles Vfor spraying the liquid into the heater, means for supplying a liquid to each of said groups, and ioat means operated by variations in such demand for controlling the flow of liquid to said nozzles and for varying the number of active nozzles, substantially as described.

8. In a liquid heater, a plurality of groups of spray nozzles adapted to permit liquid to flow simultaneously therethrough in parallel, means for producing a flow of heating medium serially through the spray produced by said nozzles, and means for individually controlling the flow to any of said groups, substantially as described.

9. In a liquid heater, a plurality of nozzles for the liquid to be hea-ted, a vapor conduit receiving the spray from said nozzles for effecting a heat interchange, and float ope-rated means for automatically varying the number of active nozzles to maintain a substantially constant pressure drop through the active nozzles, substantially as described.

10. In the method of heating liquids, the steps consisting in delivering the heating medium to a suitable container, spraying the liquid into said container through nozzles, and varying the number of active nozzles in accordance with variations in the volume of liquid being heated to thereby maintaina predetermined pressure drop through the active nozzles, substantially as described.

11. In the method of heating liquids, the steps consisting of delivering the heating medium to a suitable container, spraying the liquid into said container through a plurality of nozzle groups, and varying the number of active groups in accordance with the variations in the volume of liquid being heated to thereby maintain a predetermined pressure drop through the nozzles of the active group, substantially as described.

12. In the method of heating liquids, the

spray steps consisting in delivering the heating medium to a suitable container, spraying the liquid into said container through nozzles, and varying in predetermined sequence only the number of active nozzles in accordance With variations in the volume of liquid being heated, substantially as described.

13. In the method of heating liquids, the steps consisting in delivering the heating medium to a suitable container, spraying the liquid into said container through nozzles, varying the number of active nozzles in accordance with variations in the volume of liquid being heated to thereby maintain a predetermined pressure drop through the active nozzles, and collecting the liquid discharged from all of said nozzles in a common chamber, substantially as described.

14. In the method of heating liquids, the steps consisting of delivering the heating medium to a suitable container, spraying the liquid into said container through a plurality of nozzle groups, varying the number of active groups in accordance with the variations in the volume of liquid being heated to thereby maintain a predetermined pressure drop through the nozzles of the active group, and collecting the liquid discharged from all of said nozzles in a common chamber, substantially as described.

15. In t-he method of heating liquids, the steps consisting in delivering the heating medium to a. suitable container, spraying the liquid into said container through nozzles, varying in predetermined sequence only the number of active nozzles in accordance with variations in the volume of liquid being heated, and collecting the liquid discharged from all of said nozzles into a common chamber, substantially as described.

In testimony whereof I have hereunto set my hand.

RAYMOND N. EHRHART.

CERTIFICATE OF CORRECTION.

Patent No. 1,724,916. Granted August 20, 1929, to

RAYMOND N. EHRHART.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 103, claim 3, before the words "in regular sequence" insert "or deereasing"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 1st day of October, A. D. 1929.

M. J. Moore, {Seal} Acting Commissioner of Patents. 

